* [PATCH net-next] tcp: add ability to set a timestamp offset
@ 2013-02-11 15:50 Andrey Vagin
2013-02-11 15:50 ` [PATCH 1/3] tcp: adding a per-socket " Andrey Vagin
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: Andrey Vagin @ 2013-02-11 15:50 UTC (permalink / raw)
To: netdev
Cc: criu, linux-kernel, Andrey Vagin, David S. Miller,
Alexey Kuznetsov, James Morris, Hideaki YOSHIFUJI,
Patrick McHardy, Eric Dumazet, Pavel Emelyanov
If a TCP socket will get live-migrated from one box to another the
timestamps (which are typically ON) will get screwed up -- the new
kernel will generate TS values that has nothing to do with what they
were on dump. The solution is to yet again fix the kernel and put a
"timestamp offset" on a socket.
A socket offset is added in places where externally visible tcp
timestamp option is parsed/initialized.
Connections in the SYN_RECV state are not supported, global
tcp_time_stamp is used for them, because repair mode doesn't support
this state. In a future it can be implemented by the similar way as for
TIME_WAIT sockets.
For time-wait sockets offset is inhereted by a proper tcp_sock.
A per-socket offset can be set only for sockets in repair mode.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Andrey Vagin (3):
tcp: adding a per-socket timestamp offset
tcp: set and get per-socket timestamp
tcp: send packets with a socket timestamp
include/linux/tcp.h | 3 +++
include/uapi/linux/tcp.h | 1 +
net/ipv4/tcp.c | 11 +++++++++++
net/ipv4/tcp_input.c | 8 +++++++-
net/ipv4/tcp_ipv4.c | 12 +++++++-----
net/ipv4/tcp_minisocks.c | 3 +++
net/ipv4/tcp_output.c | 4 ++--
net/ipv6/tcp_ipv6.c | 22 +++++++++++++---------
8 files changed, 47 insertions(+), 17 deletions(-)
--
1.7.11.7
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH 1/3] tcp: adding a per-socket timestamp offset 2013-02-11 15:50 [PATCH net-next] tcp: add ability to set a timestamp offset Andrey Vagin @ 2013-02-11 15:50 ` Andrey Vagin 2013-02-11 15:50 ` [PATCH 2/3] tcp: set and get per-socket timestamp Andrey Vagin ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: Andrey Vagin @ 2013-02-11 15:50 UTC (permalink / raw) To: netdev Cc: criu, linux-kernel, Andrey Vagin, David S. Miller, Alexey Kuznetsov, James Morris, Hideaki YOSHIFUJI, Patrick McHardy, Eric Dumazet, Pavel Emelyanov This functionality is used for restoring tcp sockets. A tcp timestamp depends on how long a system has been running, so it's differ for each host. The solution is to set a per-socket offset. A per-socket offset for a TIME_WAIT socket is inherited from a proper tcp socket. tcp_request_sock doesn't have a timestamp offset, because the repair mode for them are not implemented. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> --- include/linux/tcp.h | 3 +++ net/ipv4/tcp.c | 2 ++ net/ipv4/tcp_minisocks.c | 2 ++ 3 files changed, 7 insertions(+) diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 4e1d228..974fb4a 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -162,6 +162,8 @@ struct tcp_sock { u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */ u32 lsndtime; /* timestamp of last sent data packet (for restart window) */ + u32 tsoffset; /* timestamp offset */ + struct list_head tsq_node; /* anchor in tsq_tasklet.head list */ unsigned long tsq_flags; @@ -354,6 +356,7 @@ struct tcp_timewait_sock { u32 tw_rcv_nxt; u32 tw_snd_nxt; u32 tw_rcv_wnd; + u32 tw_ts_offset; u32 tw_ts_recent; long tw_ts_recent_stamp; #ifdef CONFIG_TCP_MD5SIG diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 1ca2536..60fab09 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -400,6 +400,8 @@ void tcp_init_sock(struct sock *sk) tcp_enable_early_retrans(tp); icsk->icsk_ca_ops = &tcp_init_congestion_ops; + tp->tsoffset = 0; + sk->sk_state = TCP_CLOSE; sk->sk_write_space = sk_stream_write_space; diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index f35f2df..b94940e 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -288,6 +288,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) tcptw->tw_rcv_wnd = tcp_receive_window(tp); tcptw->tw_ts_recent = tp->rx_opt.ts_recent; tcptw->tw_ts_recent_stamp = tp->rx_opt.ts_recent_stamp; + tcptw->tw_ts_offset = tp->tsoffset; #if IS_ENABLED(CONFIG_IPV6) if (tw->tw_family == PF_INET6) { @@ -500,6 +501,7 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, newtp->rx_opt.ts_recent_stamp = 0; newtp->tcp_header_len = sizeof(struct tcphdr); } + newtp->tsoffset = 0; #ifdef CONFIG_TCP_MD5SIG newtp->md5sig_info = NULL; /*XXX*/ if (newtp->af_specific->md5_lookup(sk, newsk)) -- 1.7.11.7 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 2/3] tcp: set and get per-socket timestamp 2013-02-11 15:50 [PATCH net-next] tcp: add ability to set a timestamp offset Andrey Vagin 2013-02-11 15:50 ` [PATCH 1/3] tcp: adding a per-socket " Andrey Vagin @ 2013-02-11 15:50 ` Andrey Vagin 2013-02-11 15:50 ` [PATCH 3/3] tcp: send packets with a socket timestamp Andrey Vagin 2013-02-13 18:22 ` [PATCH net-next] tcp: add ability to set a timestamp offset David Miller 3 siblings, 0 replies; 5+ messages in thread From: Andrey Vagin @ 2013-02-11 15:50 UTC (permalink / raw) To: netdev Cc: criu, linux-kernel, Andrey Vagin, David S. Miller, Alexey Kuznetsov, James Morris, Hideaki YOSHIFUJI, Patrick McHardy, Eric Dumazet, Pavel Emelyanov A timestamp can be set, only if a socket is in the repair mode. This patch adds a new socket option TCP_TIMESTAMP, which allows to get and set current tcp times stamp. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> --- include/uapi/linux/tcp.h | 1 + net/ipv4/tcp.c | 9 +++++++++ 2 files changed, 10 insertions(+) diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index e962faa..6b1ead0 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -111,6 +111,7 @@ enum { #define TCP_QUEUE_SEQ 21 #define TCP_REPAIR_OPTIONS 22 #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */ +#define TCP_TIMESTAMP 24 struct tcp_repair_opt { __u32 opt_code; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 60fab09..9e484fc 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2706,6 +2706,12 @@ static int do_tcp_setsockopt(struct sock *sk, int level, else err = -EINVAL; break; + case TCP_TIMESTAMP: + if (!tp->repair) + err = -EPERM; + else + tp->tsoffset = val - tcp_time_stamp; + break; default: err = -ENOPROTOOPT; break; @@ -2954,6 +2960,9 @@ static int do_tcp_getsockopt(struct sock *sk, int level, case TCP_USER_TIMEOUT: val = jiffies_to_msecs(icsk->icsk_user_timeout); break; + case TCP_TIMESTAMP: + val = tcp_time_stamp + tp->tsoffset; + break; default: return -ENOPROTOOPT; } -- 1.7.11.7 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 3/3] tcp: send packets with a socket timestamp 2013-02-11 15:50 [PATCH net-next] tcp: add ability to set a timestamp offset Andrey Vagin 2013-02-11 15:50 ` [PATCH 1/3] tcp: adding a per-socket " Andrey Vagin 2013-02-11 15:50 ` [PATCH 2/3] tcp: set and get per-socket timestamp Andrey Vagin @ 2013-02-11 15:50 ` Andrey Vagin 2013-02-13 18:22 ` [PATCH net-next] tcp: add ability to set a timestamp offset David Miller 3 siblings, 0 replies; 5+ messages in thread From: Andrey Vagin @ 2013-02-11 15:50 UTC (permalink / raw) To: netdev Cc: criu, linux-kernel, Andrey Vagin, David S. Miller, Alexey Kuznetsov, James Morris, Hideaki YOSHIFUJI, Patrick McHardy, Eric Dumazet, Pavel Emelyanov A socket timestamp is a sum of the global tcp_time_stamp and a per-socket offset. A socket offset is added in places where externally visible tcp timestamp option is parsed/initialized. Connections in the SYN_RECV state are not supported, global tcp_time_stamp is used for them, because repair mode doesn't support this state. In a future it can be implemented by the similar way as for TIME_WAIT sockets. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> --- net/ipv4/tcp_input.c | 8 +++++++- net/ipv4/tcp_ipv4.c | 12 +++++++----- net/ipv4/tcp_minisocks.c | 1 + net/ipv4/tcp_output.c | 4 ++-- net/ipv6/tcp_ipv6.c | 22 +++++++++++++--------- 5 files changed, 30 insertions(+), 17 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a28e4db..dcb7a52 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3872,7 +3872,7 @@ static bool tcp_parse_aligned_timestamp(struct tcp_sock *tp, const struct tcphdr ++ptr; tp->rx_opt.rcv_tsval = ntohl(*ptr); ++ptr; - tp->rx_opt.rcv_tsecr = ntohl(*ptr); + tp->rx_opt.rcv_tsecr = ntohl(*ptr) - tp->tsoffset; return true; } return false; @@ -3896,7 +3896,11 @@ static bool tcp_fast_parse_options(const struct sk_buff *skb, if (tcp_parse_aligned_timestamp(tp, th)) return true; } + tcp_parse_options(skb, &tp->rx_opt, hvpp, 1, NULL); + if (tp->rx_opt.saw_tstamp) + tp->rx_opt.rcv_tsecr -= tp->tsoffset; + return true; } @@ -5678,6 +5682,8 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb, int saved_clamp = tp->rx_opt.mss_clamp; tcp_parse_options(skb, &tp->rx_opt, &hash_location, 0, &foc); + if (tp->rx_opt.saw_tstamp) + tp->rx_opt.rcv_tsecr -= tp->tsoffset; if (th->ack) { /* rfc793: diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 54139fa..0679fb7 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -725,7 +725,7 @@ release_sk1: */ static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack, - u32 win, u32 ts, int oif, + u32 win, u32 tsval, u32 tsecr, int oif, struct tcp_md5sig_key *key, int reply_flags, u8 tos) { @@ -746,12 +746,12 @@ static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack, arg.iov[0].iov_base = (unsigned char *)&rep; arg.iov[0].iov_len = sizeof(rep.th); - if (ts) { + if (tsecr) { rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); - rep.opt[1] = htonl(tcp_time_stamp); - rep.opt[2] = htonl(ts); + rep.opt[1] = htonl(tsval); + rep.opt[2] = htonl(tsecr); arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED; } @@ -766,7 +766,7 @@ static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack, #ifdef CONFIG_TCP_MD5SIG if (key) { - int offset = (ts) ? 3 : 0; + int offset = (tsecr) ? 3 : 0; rep.opt[offset++] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | @@ -801,6 +801,7 @@ static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) tcp_v4_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, + tcp_time_stamp + tcptw->tw_ts_offset, tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), @@ -820,6 +821,7 @@ static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, tcp_v4_send_ack(skb, (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, tcp_rsk(req)->rcv_nxt, req->rcv_wnd, + tcp_time_stamp, req->ts_recent, 0, tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->daddr, diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index b94940e..9f26eb3 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -102,6 +102,7 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, tcp_parse_options(skb, &tmp_opt, &hash_location, 0, NULL); if (tmp_opt.saw_tstamp) { + tmp_opt.rcv_tsecr -= tcptw->tw_ts_offset; tmp_opt.ts_recent = tcptw->tw_ts_recent; tmp_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; paws_reject = tcp_paws_reject(&tmp_opt, th->rst); diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 5d45159..5c6fc14 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -622,7 +622,7 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb, if (likely(sysctl_tcp_timestamps && *md5 == NULL)) { opts->options |= OPTION_TS; - opts->tsval = TCP_SKB_CB(skb)->when; + opts->tsval = TCP_SKB_CB(skb)->when + tp->tsoffset; opts->tsecr = tp->rx_opt.ts_recent; remaining -= TCPOLEN_TSTAMP_ALIGNED; } @@ -806,7 +806,7 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb if (likely(tp->rx_opt.tstamp_ok)) { opts->options |= OPTION_TS; - opts->tsval = tcb ? tcb->when : 0; + opts->tsval = tcb ? tcb->when + tp->tsoffset : 0; opts->tsecr = tp->rx_opt.ts_recent; size += TCPOLEN_TSTAMP_ALIGNED; } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 93825dd..0aa0d1d 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -712,7 +712,8 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { #endif static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win, - u32 ts, struct tcp_md5sig_key *key, int rst, u8 tclass) + u32 tsval, u32 tsecr, + struct tcp_md5sig_key *key, int rst, u8 tclass) { const struct tcphdr *th = tcp_hdr(skb); struct tcphdr *t1; @@ -724,7 +725,7 @@ static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win, struct dst_entry *dst; __be32 *topt; - if (ts) + if (tsecr) tot_len += TCPOLEN_TSTAMP_ALIGNED; #ifdef CONFIG_TCP_MD5SIG if (key) @@ -754,11 +755,11 @@ static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win, topt = (__be32 *)(t1 + 1); - if (ts) { + if (tsecr) { *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); - *topt++ = htonl(tcp_time_stamp); - *topt++ = htonl(ts); + *topt++ = htonl(tsval); + *topt++ = htonl(tsecr); } #ifdef CONFIG_TCP_MD5SIG @@ -858,7 +859,7 @@ static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb) ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - (th->doff << 2); - tcp_v6_send_response(skb, seq, ack_seq, 0, 0, key, 1, 0); + tcp_v6_send_response(skb, seq, ack_seq, 0, 0, 0, key, 1, 0); #ifdef CONFIG_TCP_MD5SIG release_sk1: @@ -869,10 +870,11 @@ release_sk1: #endif } -static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts, +static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, + u32 win, u32 tsval, u32 tsecr, struct tcp_md5sig_key *key, u8 tclass) { - tcp_v6_send_response(skb, seq, ack, win, ts, key, 0, tclass); + tcp_v6_send_response(skb, seq, ack, win, tsval, tsecr, key, 0, tclass); } static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) @@ -882,6 +884,7 @@ static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, + tcp_time_stamp + tcptw->tw_ts_offset, tcptw->tw_ts_recent, tcp_twsk_md5_key(tcptw), tw->tw_tclass); @@ -891,7 +894,8 @@ static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, struct request_sock *req) { - tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent, + tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, + req->rcv_wnd, tcp_time_stamp, req->ts_recent, tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 0); } -- 1.7.11.7 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH net-next] tcp: add ability to set a timestamp offset 2013-02-11 15:50 [PATCH net-next] tcp: add ability to set a timestamp offset Andrey Vagin ` (2 preceding siblings ...) 2013-02-11 15:50 ` [PATCH 3/3] tcp: send packets with a socket timestamp Andrey Vagin @ 2013-02-13 18:22 ` David Miller 3 siblings, 0 replies; 5+ messages in thread From: David Miller @ 2013-02-13 18:22 UTC (permalink / raw) To: avagin Cc: netdev, criu, linux-kernel, kuznet, jmorris, yoshfuji, kaber, edumazet, xemul From: Andrey Vagin <avagin@openvz.org> Date: Mon, 11 Feb 2013 19:50:16 +0400 > If a TCP socket will get live-migrated from one box to another the > timestamps (which are typically ON) will get screwed up -- the new > kernel will generate TS values that has nothing to do with what they > were on dump. The solution is to yet again fix the kernel and put a > "timestamp offset" on a socket. > > A socket offset is added in places where externally visible tcp > timestamp option is parsed/initialized. > > Connections in the SYN_RECV state are not supported, global > tcp_time_stamp is used for them, because repair mode doesn't support > this state. In a future it can be implemented by the similar way as for > TIME_WAIT sockets. > > For time-wait sockets offset is inhereted by a proper tcp_sock. > > A per-socket offset can be set only for sockets in repair mode. Series applied, thanks. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2013-02-13 18:23 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2013-02-11 15:50 [PATCH net-next] tcp: add ability to set a timestamp offset Andrey Vagin 2013-02-11 15:50 ` [PATCH 1/3] tcp: adding a per-socket " Andrey Vagin 2013-02-11 15:50 ` [PATCH 2/3] tcp: set and get per-socket timestamp Andrey Vagin 2013-02-11 15:50 ` [PATCH 3/3] tcp: send packets with a socket timestamp Andrey Vagin 2013-02-13 18:22 ` [PATCH net-next] tcp: add ability to set a timestamp offset David Miller
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